Scooterotica

Just finished mine and got about 50 or so miles on it.
4.8 on a super route pipe.
Mtech retarding from 23 degrees to 16 degrees.
30 mil phbh.
Started out x7 needle second from top,
55 pilot,
Av266,
70 choke
40 slide,
122 main
300 fuel jet.
Was running really lumpy low down and it killed a hot plug in less than 10 miles,so I dropped the pilot to a 53 and dropped the needle by a half using one of those little washer things.
Initially that cleaned it up but it's gone back to being lumpy...feels really rich.
Jetting is something I've always struggled with.
Any ideas on what I should do should I keep dropping down on the pilot or go for a leaner needle,if I have my facts right an x13 is leaner?
Any help is greatly appreciated.

Super tourer pipe...not route.

I ran my Avanti for 3 years, continuously fighting the low down bogginess, some modifications/adjustments worked better than others.......I've just fitted a Mikuni TMX 35 and I would suggest that is the solution. The bottom end difference is amazing, just hope the top end performs as well !!

Saying all that the other 2 Avantis that I ride with seem a lot cleaner at the bottom end than mine did, all very similar set-ups so who knows ?

1 do have a TMX35 on my TS1 that I could use,but I don't yet feel I've finished with the delly yet.
Interesting tho.

monkey boy wrote:Just finished mine and got about 50 or so miles on it.
4.8 on a super route pipe.
Mtech retarding from 23 degrees to 16 degrees.
30 mil phbh.
Started out x7 needle second from top,
55 pilot,
Av266,
70 choke
40 slide,
122 main
300 fuel jet.
Was running really lumpy low down and it killed a hot plug in less than 10 miles,so I dropped the pilot to a 53 and dropped the needle by a half using one of those little washer things.
Initially that cleaned it up but it's gone back to being lumpy...feels really rich.
Jetting is something I've always struggled with.
Any ideas on what I should do should I keep dropping down on the pilot or go for a leaner needle,if I have my facts right an x13 is leaner?
Any help is greatly appreciated.

Must say I'm surprised you're boggy low down with a 53 pilot & x7 needle on what is in effect 1 & 1/2 clip down (if I've understood you with the little washer?), especially with an mtech fitted. Mines fairly crisp on a 54 pilot, av266 atomizer, x7 needle 2nd clip down, the difference being my slightly leaner 45 slide to your 40. It sounds from previous poster Mick1 that the Mikuni tmx has transformed his low down problem, however if you've not got the funds at the mo, you could try changing the slide, still not cheap compared to jets, but it might just clean it up a bit. I use 'Wasp' for my delly spares. Good luck.

Bert Oni wrote:

monkey boy wrote:Just finished mine and got about 50 or so miles on it.
4.8 on a super route pipe.
Mtech retarding from 23 degrees to 16 degrees.
30 mil phbh.
Started out x7 needle second from top,
55 pilot,
Av266,
70 choke
40 slide,
122 main
300 fuel jet.
Was running really lumpy low down and it killed a hot plug in less than 10 miles,so I dropped the pilot to a 53 and dropped the needle by a half using one of those little washer things.
Initially that cleaned it up but it's gone back to being lumpy...feels really rich.
Jetting is something I've always struggled with.
Any ideas on what I should do should I keep dropping down on the pilot or go for a leaner needle,if I have my facts right an x13 is leaner?
Any help is greatly appreciated.

Must say I'm surprised you're boggy low down with a 53 pilot & x7 needle on what is in effect 1 & 1/2 clip down (if I've understood you with the little washer?), especially with an mtech fitted. Mines fairly crisp on a 54 pilot, av266 atomizer, x7 needle 2nd clip down, the difference being my slightly leaner 45 slide to your 40. It sounds from previous poster Mick1 that the Mikuni tmx has transformed his low down problem, however if you've not got the funds at the mo, you could try changing the slide, still not cheap compared to jets, but it might just clean it up a bit. I use 'Wasp' for my delly spares. Good luck.

Oh btw, I'm pretty certain x13 is richer than x7.

mick1 wrote:I ran my Avanti for 3 years, continuously fighting the low down bogginess, some modifications/adjustments worked better than others.......I've just fitted a Mikuni TMX 35 and I would suggest that is the solution. The bottom end difference is amazing, just hope the top end performs as well !!

Saying all that the other 2 Avantis that I ride with seem a lot cleaner at the bottom end than mine did, all very similar set-ups so who knows ?

What length con-rods are you and your buddies running?

SF

all standard cranks and rods (57x107)..........but I've bought another kit and i'm looking at a 60 crank with a 110 con-rod for this build

Are you running a longer con-rod ?

A longer rod increases inlet duration.
I wondered if you were using a longer rod than your mates that I could be a reason for your boggier bottom.

SF

Good call and the timings may be slightly different with the casings used. All squishes are between 1.2 and 1.5 but the difference could also be on the inlet duration....never really thought of that before.......cheers

Kebabs and takeaways are the main cause of my boggy bottom